JPH0129457B2 - - Google Patents

Description

BACKGROUND OF THE INVENTION Field of the Invention This invention relates to optical signal transmitting and receiving apparatus. More specifically, the present invention relates to an optical signal transmitting/receiving device that transmits and receives signals between a terminal device and a modem, or between terminal devices or modems using light.

Explanation of Prior Art Data terminal equipment used in data transmission equipment, etc. is generally
Many use the RS232C standard interface defined by This interface includes
A connector containing 25 connection pins is provided, and the signal given to each connection pin is according to the device specifications.
Depends on DTE and modem specification DCE. That is, in general, a computer has device specifications, and a data communication control device has modem specifications. However, terminal devices often have device specifications or modem specifications, and when connecting such terminal devices, it is necessary to check whether the terminal devices are device specifications or modem specifications. You may need to change the connection cable depending on the situation.

Figures 1 to 3 are diagrams for explaining the method of connecting cables in a data terminal device, which is the background of this invention. In particular, Figure 1 shows how to connect a terminal device with device specifications and a terminal device with modem specifications. FIG. 2 shows a case in which terminal devices having device specifications are connected to each other, and FIG. 3 shows a case in which terminal devices having modem specifications are connected to each other. FIG. 4 is a schematic block diagram of a device for optically transmitting and receiving signals applied to each connection pin of a connector using an optical fiber.

First, with reference to FIG.
In this case, a sending signal SD or the like is given as an output signal to the 2nd pin, 4th pin, etc., and a receiving signal RD etc. is given as an input signal to the 3rd pin, 5th pin, etc. On the other hand, the receptacle 21 of the connector provided in the terminal device 2 with modem specifications has the 2nd pin,
The input signal is given to the 4th pin..., and the 3rd pin, 5th pin...
An output signal is given to pin No. Therefore, when connecting the terminal devices 1 and 2, plugs 3 and 4 are connected to both ends of the multi-core cable 5.
are connected so that their respective connection pins are 1:1, plug 3 is connected to receptacle 11, and plug 4 is connected to receptacle 11.
may be connected to the receptacle 21.

However, when connecting terminal devices 1a and 1b with device specifications as shown in FIG.
Each connecting pin of plugs 3 and 4 as shown in the figure is 1
It is not possible to use cables 5 that are connected one-to-one. This is because pins 2 and 4 of the receptacle 11a of the terminal device 1a are given output signals, and connection pins 2 and 4 of the receptacle 11b of the terminal device 1b are also given output signals. This is because Therefore, in order to connect the terminal devices 1a and 1b of the device specifications to each other in this way, the 2nd pin of the plug 6 and the 3rd pin of the plug 7, the 3rd pin of the plug 6 and the 3rd pin of the plug 7,
It is necessary to use a multi-core cable 8 that alternately connects the second pin of the two pins. Similarly, when connecting receptacles 2a and 2b to a terminal device with modem specifications as shown in FIG.
Input signals are given to the 2nd pin, 4th pin, etc. of 1b, and output signals are given to the 3rd pin, 5th pin, etc., so in the same way as explained in Fig. 2. It is necessary to use a cable 8 in which pins 2 and 3 are alternately connected.

By the way, the terminal devices 1 and 2 or 1a and 1b or 2a explained in FIGS. 1 to 3 above
and 2b, it is necessary to use an optical signal transmitting/receiving device 9 as shown in FIG. This optical signal transmitting/receiving device 9 has a receptacle 91
A multiplexing circuit 92 multiplexes the input signals applied to the multiplexing circuit 92, outputs an optical signal from an optical transmitter 93, and transmits the optical signal to the other party's optical signal transmitting/receiving device via an optical connector 94 and an optical fiber 95. Further, the optical signal transmitted from the other party's optical signal transmitting/receiving device is transmitted to the optical receiver 98 via the optical fiber 97 and the optical connector 96.
received at The output of the optical receiver 98 is sent to the demodulation circuit 9
9 and applied to the connection pin of the receptacle 91.

Even when using the optical signal transmitting/receiving device 9 described above, when interconnecting terminal devices with device specifications or terminal devices with modem specifications, the second
It was necessary to use a cable in which the core wires were alternately connected to connecting pins as shown in FIG. 3 and FIG. For this purpose, each core wire has one
Two types of cables must be prepared: one connected in pairs and one connected alternately.If the wrong cable is selected, the output end of the output circuit built into the terminal device may be short-circuited. There is a risk that the product may deteriorate and cause a malfunction. Furthermore, when there are a large number of terminal devices, it is necessary to prepare a large number of two types of cables, which is extremely inconvenient.

SUMMARY OF THE INVENTION Therefore, the main object of the present invention is to enable the use of any combination of terminal devices provided with connectors to which input/output signals are given to connection pins specified in device specifications or modem specifications. To provide an optical signal transmitting/receiving device which can be connected by simply switching a switch without using a special cable or a switch, and can transmit and receive signals between the two by light.

To summarize the invention, a set of optical transmitting/receiving units is provided, and each optical signal transmitting/receiving unit transmits a signal sent to one of at least one pair of connecting pins included in the connector to a first one. Select with switch,
This signal is multiplexed with a signal applied to a connection pin other than at least one pair of connection pins, and this signal is transmitted as an optical signal to the other optical transmitter/receiver. The optical receiving means receives the optical signal transmitted from the other optical transmitter/receiver, demodulates the output, selects the demodulated output by the second switch operating in conjunction with the first switch, and at least It is configured to be applied to the other of a pair of connection pins.

Therefore, according to the present invention, the signals given to the connection pins can be exchanged simply by switching the first and second switches, so that it is possible to exchange the signals given to the connection pins by simply switching the first and second switches, so that it is possible to exchange the signals given to the connection pins by simply switching the first and second switches. Just by preparing one, you can connect both modem specifications and device specifications, modem specifications to each other, and device specifications to each other.

According to a preferred embodiment of the invention, the signal selected by the first switch and the signal applied to at least one pair of pins other than the connecting pins are time-division multiplexed, so that Even if the number of types of signals provided increases, many signals can be transmitted and received by one set of optical transmitting and receiving sections.

The present invention will be described in more detail below along with embodiments shown in the drawings.

DESCRIPTION OF THE EMBODIMENT FIG. 5 is a schematic block diagram of an embodiment of the present invention. First, the general structure of this embodiment will be explained with reference to FIG. FIG. 5 shows an example of transmitting and receiving signals between the local terminal device 20a and the opposite terminal device 20b. For this purpose, the local terminal device 20a and the opposite terminal device 20a
A pair of optical transmitting/receiving sections 30a and 30b is provided between the optical transmitter and the optical transmitter/receiver 30b. One optical transmitter/receiver 30a is connected to its own terminal device 20a by a multicore cable with plugs 3 and 4 connected to both ends thereof. Similarly, the other optical transmitter/receiver 30b is connected to the other party's terminal device 20b by a cable 5 having plugs 3 and 4 connected to both ends thereof. Optical transmitter/receiver 30a
The switch 310, the transmitter 320, and the receiver 330
including. The switch 310 is, for example, connected to connection pin 2.
This is to alternately switch between No. 3 and No. 3.
One set of optical transmitting/receiving sections 30a and 30b is an optical connector 4.
1 and 43 are connected to both ends of the optical fiber 4.
2 and optical connectors 44 and 46 are connected by an optical fiber 45 connected to both ends thereof. Therefore, by simply switching the switches 310, 310 of each optical transmitting/receiving section 30a and 30b, the output signal from the local terminal device 20a can be transmitted to the other terminal device 20b.
is given as an input signal to the opposite station terminal device 20.
The output signal from terminal b can be given as an input signal to the local terminal device 20a.

FIG. 6 is a concrete block diagram of one embodiment of the present invention. First, the configuration of an embodiment of the present invention will be described with reference to FIG. Optical transmitter/receiver 3
0 connects the cable 5 to the terminal device 20a or 20b.
includes a receptacle 300 connected by.
This receptacle 300 includes pins 1 to 25, pins 2 and 3, pins 4 and 5.
Pin No. 6, pin No. 7, pin No. 7, etc. each form a pair. Pins 2, 4, and 6 are connected to common contacts of switches 311 to 313, respectively, and pins 3, 5, and 7 are connected to common contacts of switches 314 to 316, respectively. Switches 311-313 constitute a first switch, and switches 314-316 constitute a second switch. Each of these switches is configured to switch to the A side contact or the B side contact in conjunction with each other. The A-side contacts use each connection pin for device specifications, and the B-side contacts use them for modem specifications. switch 311
The B side contacts of switches 314 to 313 are connected to the A side contacts of switches 314 to 316, and are also connected to the input of a selector 321 as selection means.

The selector 321 is for time-divisionally selecting and multiplexing each signal input via the switch 310. For this purpose, a clock generation circuit 322 for generating clock pulses is provided, and the clock pulses are sent to a counter 323 as a counting means.
given to. Counter 323 counts clock pulses and provides the counted value to selector 321. The input signal multiplexed by the selector 321 is D
applied to the D input of type flip-flop 324. A clock pulse is applied from a clock generation circuit 322 to a clock pulse input terminal of a D-type flip-flop 324. This D type flip-flop 324 synchronizes the output of the selector 321 with the clock pulse. The Q output of the D-type flip-flop 324 is given to one input terminal of an AND gate 327, and the output is an AND gate.
It is applied to one input terminal of gate 328.

The clock pulses from the clock generation circuit 322 are sent to monostable multivibrators 325 and 3.
26 is also given. The monostable multivibrator 325 generates a relatively long pulse signal at the timing of the leading edge of the clock pulse.
It is applied to the other input terminal of AND gate 327. This monostable multivibrator 325 opens the AND gate 327 when the Q output of the D-type flip-flop 324 is at a high level. Monostable multivibrator 326
generates a relatively short width pulse signal at the timing of the leading edge of the clock pulse and outputs the AND gate 328.
is applied to the other input terminal of . This monostable multivibrator 326 opens an AND gate 328 when the output of the D-type flip-flop 324 is at a high level. AND gate 32
Each output of 7 and 328 is an OR gate 329
A light emitting diode 34 as a light transmitting means via
given to 0. The light emitting diode 340 transmits the input signal as an optical signal to the transmitting/receiving unit of the other station.

A photodiode 331 serving as an optical receiving means converts an optical signal transmitted from an optical transmitting/receiving section of a partner station into an electrical signal, and its output is input to and connected to a monostable multivibrator 332 included in a demodulating means 30. type flip flop 3
It is applied to each D input terminal of 35 to 337. The monostable multivibrator 332 generates a timing signal based on the output of the photodiode 331. This timing signal is given to counter 333. The counter 333 counts the timing signals and sends the counted value to the decoder 33.
4 to generate clock pulses necessary to time-divisionally demodulate the output signal of the photodiode 331. Each clock pulse is applied to a clock pulse input of a D-type flip-flop 335-337. D-type flip-flops 335-337 set the outputs of photodiodes 331 based on clock pulses from decoder 334, and apply their respective outputs to the B contacts of switches 311-313.

FIG. 7 is a waveform diagram for explaining the operation of each part in FIG. 6, and FIG. 8 is a diagram for explaining the flow of signals at pins 2 and 3 when the switch 310 is switched. .

Next, the specific operation of FIG. 6 will be explained with reference to FIGS. 7 and 8. If both the current terminal device 20a and the partner terminal device 20b shown in FIG. 5 have device specifications, switches 311 to 316 are switched to the A side. Then, the input signal given to pin 2 (Fig. 7a) is sent to the switch 311.
selector 321 via the A side contact from the common contact of
is input. Similarly, the input signal input to the No. 4 pin (FIG. 7b) is input from the common contact of the switch 312 to the selector 321 via the A-side contact. The selector 321 is the clock generation circuit 32
The input signals input to pins 2 and 4 are sequentially selected based on the count value of counter 323 that counts clock pulses from pin 2 (FIG. 7c). The signal selected by selector 321 (FIG. 7d) is applied to the D input of D type flip-flop 324. D type flip-flop 324
synchronizes the output signal of the selector 321 with the clock pulse, and generates the signal shown in FIG. 7e from the Q output.
The signal shown in FIG. 7f is applied to an AND gate 328.

On the other hand, monostable multivibrator 32
5 is a timing signal (Fig. 7g) that remains at a high level for a relatively long period from the leading edge of the clock pulse.
Similarly, the monostable multivibrator 326 sends a timing signal (h in FIG. 7) which becomes high level for a relatively short period from the leading edge of the clock pulse to the AND gate 327.
Give to 28. Therefore, AND gate 327
The gate is opened only during the period when the Q output of the D-type flip-flop 324 is at a high level and the timing signal from the monostable multivibrator 325 is at a high level. Similarly,
AND gate 328 opens only while the output of D-type flip-flop 34 is high and the timing signal from monostable multivibrator 326 is high.
Therefore, the OR gate 329 provides a multiplexed signal to the light emitting diode 340 which is synchronized with the input signals inputted to pins 2 and 4, ie, the clock pulse, as shown in FIG. 7i. Light emitting diode 340 blinks in response to the multiplexed signals. The optical signal from the light emitting diode 340 is given to the optical transmitter/receiver 30b of the other station via the optical connector 41, the optical fiber 42, and the optical connector 43, as shown in FIG.

On the other hand, the input signals inputted to the 2nd and 4th pins from the partner station terminal device 20b are transmitted from the optical transmitter/receiver 30b to the optical connector 4 in the same manner as described above.
6. The signal is input via the optical fiber 45 and the optical connector 44 to the photodiode 331 of the optical transmitter/receiver 30a on the local side. Photodiode 331 converts the input optical signal into an electrical signal and supplies it to monostable multivibrator 332 and each D input of D type flip-flops 335 to 337. Monostable multivibrator 33
2 generates a timing pulse (FIG. 7j) synchronized with the trailing edge of the received signal shown in FIG. 7i and supplies it to the counter 333. Counter 333 counts the timing signals and provides them to decoder 334. The decoder 334 decodes the count signal input from the counter 333 and supplies the signals k, l, . . . in FIG. 7 to the D-type flip-flops 335 to 337, respectively. A D-type flip-flop 335 sets the output of photodiode 331 on the trailing edge of the timing signal from decoder 334. That is, since the output of the photodiode 331 is at a low level at the trailing edge of the timing signal, the output is set at a high level (FIG. 7m). D
The output of type flip-flop 335 is applied to the B side contact of switch 311 and the A side contact of switch 314;
is switched to the A side, so it is not applied to the 2nd pin but is applied to the 3rd pin.

In this way, if both the own station terminal device 20a and the opposite station terminal device 20b have device specifications, the input signal given to the second pin of the own station is output from the third pin of the opposite station, and The input signal applied to pin No. 3 can be output from pin No. 3 of the local station. If the local terminal device 20a has device specifications and the partner terminal device 20b has modem specifications, it is sufficient to switch the switch 310 of the local terminal to the A side and the switch of the partner terminal to the B side. In this way, the signal input to the second pin of the own station can be output from the second pin of the other station. That is, the input signal applied to pin 2 of the own station is applied from the common contact of the switch 311 to the selector 321 via the A side contact, but in the optical transmitting/receiving section of the other station, the switch 310 is switched to the B side contact. Therefore, the output of the D type flip-flop 335 is applied to the second pin via the B side contact and the common contact of the switch 310.

Conversely, if the terminal device 20a of the local station is of modem specification and the terminal device 20b of the other station is of device specification, if the switch 310 of the local station is switched to the B side and the switch of the other station is switched to the A side. good. Furthermore, if both the terminal device 20a of the local station and the terminal device 20b of the opposite station have modem specifications, it is sufficient to switch both switches 310 to the B side.

As described above, according to this embodiment, by simply switching the switches 310 of the optical transmitter/receivers 30a and 30b of the local station and the other station, the signals given to pins 2 and 3 can be arbitrarily changed as shown in FIG. can be switched to Therefore, there are two different connection modes as explained in FIGS. 1 and 2.
There is no need to prepare different types of cables.

In the above embodiment, the case where the input signals applied to the 2nd pin and the 4th pin are multiplexed is explained. A given signal is selected by the switch 30, a signal given to other connection pins, such as pin 10, is given directly to the selector 321 without being switched by the switch 310, and these two signals are multiplexed. It's okay.

As described above, according to the present invention, the first switch selects a signal given to one of at least one pair of connection pins, and the selected signal and the signal given to the other connection pin are combined. The optical signal transmitted from the other optical signal transmitting/receiving unit is received and demodulated, and the demodulated output is switched by a second switch, and one of at least one pair of connection pins is multiplexed with the signal and transmitted optically. Since the configuration is such that the output signal of the local station is applied to the other connection pin of the other station, even if the local station and the other station have different or the same combination of device specifications or modem specifications, the output signal of the local station can be applied as the input signal of the other station. , and conversely, the output signal of the other station can be received as the input signal of the own station. This eliminates the need to prepare two types of connection cables with different connection modes.

[Brief explanation of drawings]

Figures 1 to 3 are diagrams for explaining the method of connecting cables in data terminal equipment, etc., which is the background of this invention. In particular, Figure 1 shows the case of device specifications and modem specifications, and Figure 2 shows the case of device specifications and modem specifications. 3 shows the case where the device specifications are the same, and FIG. 3 shows the case where the modem specifications are the same. FIG. 4 is a schematic block diagram of a device that transmits and receives signals using optical fibers and signals applied to each connection pin of a connector. FIG. 5 is a schematic block diagram of the present invention. FIG. 6 is a concrete block diagram of one embodiment of the present invention. 7th
This figure is a waveform diagram for explaining the operation of FIG. 6. Figure 8 shows 2 cases when the switch is changed.
FIG. 3 is a diagram for explaining the flow of signals between pin No. 3 and pin No. 3;

Claims (1)

[Claims] 1. An optical signal transmitting/receiving device including a pair of optical transmitting/receiving units for transmitting and receiving signals by light between each optical signal transmitting/receiving unit, wherein each optical signal transmitting/receiving unit has a plurality of connection pins. a connector, of which at least one pair of connection pins receives a transmission signal and a reception signal; a first switch for selecting a signal sent to one of the connection pins of the at least one pair of connection pins; , multiplexing means for multiplexing the signal selected by the first switch and the signal applied to the connection pins other than the at least one pair of connection pins; an optical transmitting means for transmitting to the optical signal transmitting/receiving section; an optical receiving means for receiving the optical signal transmitted from the other optical signal transmitting/receiving section; a demodulating means for demodulating the output of the optical receiving means; and the first switch. a second one for operating in conjunction with the other for providing the output signal of the demodulating means to the other one of the at least one pair of connecting pins;
Optical signal transmitter/receiver equipped with a switch. 2. The multiplexing means includes time division multiplexing means for time division multiplexing the signal selected by the first switch and the signal applied to the at least one pair of pins other than the connection pins. 2. The optical signal transmitting/receiving apparatus according to claim 1, wherein the demodulating means includes means for time-divisionally demodulating the output of the optical receiving means. 3. The multiplexing means includes: a clock signal generating means for generating a clock signal; a counting means for counting the output of the clock signal generating means; and a signal selected by the first switch based on the output of the counting means. 3. The optical signal transmitting/receiving apparatus according to claim 2, further comprising selection means for sequentially selecting signals applied to pins other than the at least one pair of connection pins.